unifhycontrib.rfm

class unifhycontrib.rfm.OpenWaterComponent

River flow model (RFM) is a runoff routing model based on a discrete approximation of the one-directional kinematic wave with lateral inflow (Bell et al., 2007, Dadson et al., 2011).

The wave equation is parametrised differently for surface and sub-surface pathways, themselves split into a land domain, and a river domain. Return flow is also possible between surface and sub-surface pathways in each domain.

This Python implementation of RFM is based on the work by Huw Lewis.

Contributors

Huw Lewis [1]

Affiliations
  1. UK Met Office

Licence

UK Open Government

Copyright

2020, UK Met Office

Inputs

name

flow_accumulation

units

1

kind

static

description

drainage area (specified in number of cells) draining to a grid box

Inwards

name

surface_runoff_flux_delivered_to_rivers

units

kg m-2 s-1

from

subsurface

method

mean

name

net_groundwater_flux_to_rivers

units

kg m-2 s-1

from

subsurface

method

mean

Outputs

name

outgoing_water_volume_transport_along_river_channel

units

m3 s-1

description

streamflow at outlet of grid element

Parameters

name

c_land

units

m s-1

description

kinematic wave speed for surface flow in a land grid box on the river routing grid

name

cb_land

units

m s-1

description

kinematic wave speed for subsurface flow in a land grid box on the river routing grid

name

c_river

units

m s-1

description

kinematic wave speed for surface flow in a river grid box on the river routing grid

name

cb_river

units

m s-1

description

kinematic wave speed for subsurface flow in a river grid box on the river routing grid

name

ret_l

units

1

description

land return flow fraction (resolution dependent)

name

ret_r

units

1

description

river return flow fraction (resolution dependent)

name

routing_length

units

m

description

length of the routing path

Constants

name

a_thresh

units

1

description

threshold drainage area (specified in number of cells) draining to a grid box, above which the grid cell is considered to be a river point - remaining points are treated as land (drainage area = 0) or sea (drainage area < 0)

default_value

1.3e+01

name

rho_lw

description

specific mass of liquid water

units

kg m-3

default_value

1.0e+03

States

name

flow_in

units

m3

description

surface flow from neighbouring cells

name

b_flow_in

units

m3

description

sub-surface flow from neighbouring cells

name

surf_store

units

m3

description

surface water store

name

sub_store

units

m3

description

sub-surface water store

SpaceDomain Properties

name

land_sea_mask

required

False

name

flow_direction

required

True

name

cell_area

required

True